1. Formation of Igneous Rocks

2. Formation of Igneous Rocks
Source
Molten Rock
Composition
(3 Components)
Liquid
Solid
Volatiles
Creation
Juvenile Material
Remelting Rock
Water/Volatile Addition
Roll of Temperature and Pressure
Location
Beneath Surface (Intrusive)
Magma
Very-slow cooling
Large Crystals
At Surface (Extrusive)
Lava
Slow cooling
Small Crystals
Above Surface (Extrusive)
Pyroclastics
Very-fast cooling
Exposure to air
Exposure to water
No Crystals

15. MAGMA CRYSTALIZATION

24. Where Igneous Rocks Form

25. Igneous Rock Formation
Magma
Molten rock beneath earth’s surface
It is less dense than surrounding rock, so it rises (like ice in a Coke®)
Lava
Molten rock at or near earth’s surface
As molten rock cools, it forms IGNEOUS ROCK

28. Igneous Rock Formation
INTRUSIVE igneous rock
Forms when magma cools and hardens beneath the earth’s surface.
Coarse (large) grained rock, because the crystals (xtls) have more time to grow
EX: granite, diorite, gabbro

29. Igneous Rock Formation
EXTRUSIVE igneous rock
Forms when lava cools and hardens near the earth’s surface.
Fine (small) grained rock, because the crystals (xtls) don’t have time to grow very large
EX: rhyolite, andesite, basalt

30. Igneous Rock Formation
PYROCLASTIC Igneous Rock
Forms when lava cools instantly as it hits air or water at the surface of the earth
No crystals at all
May have holes (porous) because gases don’t have time to escape before lava cools.
EX: scoria, pumice, obsidian

31. PYROCLASTIC EXTRUSIVE INTRUSIVE scoria, obsidian, pumice rhyolite
andesite
basalt
INTRUSIVE
granite, diorite, gabbro

32. THE END